Improvement in hot-air furnaces



2 Sheets-Sheet Z.

cf cLARK. HOT-AIRv FURNACE.

110.171,351. j Patented Dec. 21,1875.

"l-lll UNITED STATES PATENT OFFICE. i

CHARLES CLARK, OF MINNEAPOLIS, MINNESOTA.

IMPROVEMENT IN HOT-AIR FURNACEYS.

Specification forming part of Letters Patent N0. 171,351, dated December 21, 1875; application filed October 22, 1875.

To all whom Iit may concern: i

Be it known that I, CHARLES CLARK, of Minneapolis, Minnesota, have invented a new and useful Improvement in Hot- Air Furnaces, of which the following is a full, clear, and ex act description, reference being had to the accompanying drawings, making a'part of this specification, in Which- Figure l represents a perspective View of a hot-air furnace with only one side ofthe brick Wall, and with my improvements attached. Fig. 2 is a longitudinal section. Fig. 3 is a cross-section through a: x. Fig. 4 is a crosssection through y 1 My invention relates to that class of furnaces designed for heating air to warm'dwellings and other buildings, and is an improve ment` on Patent No. 153,537, issued to me on the 28th day ot' July, 1874. It consists in the combination of devices hereinafter described and explained.

To enable others skilled in the art to make and use my invention, I Will proceed ,to describe the exact manner in which I have carried it out.

In the drawings, A represents the outside wall of a furnace, constructed with internal air-chambers a, communicating withV the outside air by means of the pipes a', provided with registers a". The air-chamber a also communicates with the tire-box B through the pipes b b. The shell of the fire-box is made ill the usual manner, and is provided with a removable grate-lining, C, conveniently made in sections, that itmay be readily replaced or changed. Extending longitudinally along the side of the lire-box are secured the semi-cylindrical perforated air-chambers c e, the perforations in each being at points opposite to the spaces between the bars of the grate-lining C, so as to admit the jets of air directly to the re, between the grates of the lining. These air-chalnbcrs being' semi-cylindrical on their inner side, the jets of air pass radially to the fire, and necessarily strike it atv every point, and the air-chambers being placed on a line near or above the center of the re not only tends to preserve both the grating and the shell from the injurious effects of heat, but, supplying fresh oxygen at every point of the fire-box, causes a more complete combustion of the gases and particles of fuel, which would otherwise pass oft' with smoke, thus effecting a great saving in utilizing what would otherwisebe lost.

Through the sides of the radiator D, located above the nre-box B, I construct a series of vertical air-dues, d d, by which I secure a.

drums G, whence it passes off through the tubesv H I I to the division c of the radiator D, and thence through the chimney L.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

l. In a hot-air furnace, the lire-box B, providedvwith the horizontal semi-cylindrical perforated air-chambers e e, in combination with `the gratelining C and air-pipes b b, substantially as and for the purpose set forth. l

2. The lire-box B, provided with the semicylindrical perforated air-chambers c e, gratelining C, and air-pipes b b, in combination with the radiator D, provided with vertical flues d d, the diaphragm E, provided with the damper c, and the tlues j' f, horizontal drums G, and tubes H H, all constructed to operate 'substantially as and for the purpose set forth.

In testimony that I claim the foregoing I have hereunto set my hand. l

CHARLES CLARK. 

